Scope Of Spread Research Articles

Impact of individual interest shift on information dissemination in modular networks

Social networks exhibit strong community structure. Many researches have been done to explore the impacts of community structure on information diffusion but few combined with human behaviors together. In this paper, we focus on how the individual interests’ changing behavior impacts the dynamics of information propagation. Firstly, we propose an information dissemination model considering both the community structure and individual interest shift where social reinforcement and time decaying are taken into account. The accuracy of the model is evaluated by comparing the simulation and theoretical results. Further, the numerical results illustrate that both the community structure and the interests changing behavior have effects on the outbreak size of the information dissemination. Specially, lower modularity and higher community connection density will accelerate the speed of information propagation especially when the information maximal lifetime is shorter. In addition, the changes of individual interests in the message have a great impact on the final density of the received through increasing or decreasing the number of satisfied individuals directly. What is more, our findings suggest that when the modularity of the network is higher and the community clustering coefficient is lower individual interest shift behavior will have a heavier effect on the spread scope.

Modeling information diffusion on microblog networks based on users' behaviors

Online social networks, such as Facebook, Twitter and YouTube, play a vital role in information sharing and diffusion, and recently many dynamics models on social networks have been proposed to model information diffusion. However most models are theoretical, their parameters do not come from realistic data and their validity and reliability have not been evaluated empirically. In the paper we first analyze the users' behaviors of reading and reposting microblog in Sina Weibo, a Twitter-like website in China, and find that users' number of fans, the average reposted number of users' microblog, the intensity of users' interaction and the similarity between microblog topics and users' topic interests can significantly influence reposting behavior. Then we propose an information diffusion model Susceptible-Infected-Recovered based on Users' Behaviors (SIRUB) on microblog networks, compute the users' probability of reading microblog in the model according to the probability of their logging on microblog in a day, and obtain the reposting probability utilizing the logistic regression which considers 16 possible factors influencing users' reposting behavior. The 16 factors can be divided into three categories: the characteristics of microblog publishers, microblog text features and social relationship characteristics. We utilize the beginning 2/3 microblog data to obtain model parameters and logistic regression coefficients, and the remaining 1/3 data to examine the validity of the model. The experiments on Sina Weibo network show that the model can predict users' reposting behavior accurately only when it considers both reading and reposting probabilities. F-score which considers precision and recall is used to assess prediction effect of the model. The highest F-score for the prediction of SIRUB model on users' reposting behavior is 0.228 which is much larger than those of classical Susceptible-Infected-Recovered (SIR, F-score=0.039) and Susceptible-Infected-Contacted-Recovered (SICR, F-score=0.037) models. The prediction on the spreading scope of microblog for SIR and SICR models is related with users' number of fans while for SIRUB model not. For SIRUB model the mean and standard deviation of the errors of prediction on spreading scope are smaller than those of SIR and SICR models. These results indicate that users' behaviors of reading and reposting microblog should be appropriately taken in account when modeling information diffusion on microblog networks, and that, in general, the prediction performance of the data-driven SIRUB model proposed in the paper is better than those of SIR and SICR models regardless of the prediction of users' reposting behavior or diffusion scope of microblog.

Bacillus thuringiensisConjugation in Simulated Microgravity

Spaceflight experiments have suggested a possible effect of microgravity on the plasmid transfer among strains of the Gram-positive Bacillus thuringiensis, as opposed to no effect recorded for Gram-negative conjugation. To investigate these potential effects in a more affordable experimental setup, three ground-based microgravity simulators were tested: the Rotating Wall Vessel (RWV), the Random Positioning Machine (RPM), and a superconducting magnet. The bacterial conjugative system consisted in biparental matings between two B. thuringiensis strains, where the transfer frequencies of the conjugative plasmid pAW63 and its ability to mobilize the nonconjugative plasmid pUB110 were assessed. Specifically, potential plasmid transfers in a 0 g position (simulated microgravity) were compared to those obtained under 1 g (normal gravity) condition in each device. Statistical analyses revealed no significant difference in the conjugative and mobilizable transfer frequencies between the three different simulated microgravitational conditions and our standard laboratory condition. These important ground-based observations emphasize the fact that, though no stimulation of plasmid transfer was observed, no inhibition was observed either. In the case of Gram-positive bacteria, this ability to exchange plasmids in weightlessness, as occurs under Earth's conditions, should be seen as particularly relevant in the scope of spread of antibiotic resistances and bacterial virulence.

A Typological Study of Tonal Systems of Japanese and Prinmi: Towards a Definition of Pitch-accent Languages

Based on the principle of suprasegmental organization in Japanese and Prinmi (a Tibeto-Burman language of China), this paper defines a ‘pitch-accent system’ as one that generates tonal patterns through different placement of a marked tone on a syllable/mora in an underlying domain, which is independent of both the syllable and the word. Under this definition, the pitch-accent systems of six Japanese dialects can be analyzed uniformly. The diversity of the pitch-accent systems between these Japanese dialects and Prinmi is mainly reflected in: (1) whether or not the marked tone spreads; (2) the direction of spreading and restriction on the scope of spreading; and (3) which edge of the underlying domain is relevant in locating the marked tone.